High binder flame-retardant nonwovens

ABSTRACT

The present invention concerns a flame-retardant (FR) nonwoven fabric/article useful in household goods and particularly for mattresses. The nonwoven fabric/article comprises from about 6 to about 40 weight percent of a low melt binder; at least one of FR rayon fiber, FR acrylic fiber, FR melamine fiber, FR polyester fiber, and FR coated fiber; and optionally a synthetic and/or natural fiber. From this nonwoven fabric/article, many household goods such as drapes, curtains, rugs, bedding, and particularly mattresses may be constructed. The present invention also contemplates a mattress constructed from the nonwoven fabric/article comprising FR rayon fibers, FR acrylic fibers, FR melamine fiber, FR polyester fiber, and FR coated fiber, non-FR fibers, and about 6 to about 40 weight percent of a low melt binder. The mattress from this construction passes the California Test Bulletin 129 stringent conditions for mattresses used in public places. Preferably, the nonwoven fabric/article of the present invention has a batt weight of at least 4 oz./sq. yd. and preferably between 4 oz./sq. yd. and 20 oz./sq. yd.

CROSS-REFERENCE TO RELATED APPLICATION

This is a continuation-in-part of U.S. patent application Ser. No.10/298,990, filed Nov. 18, 2002, and entitled “FLAME-RETARDANTNONWOVENS.”

BACKGROUND OF THE INVENTION

1) Field of the Invention

The present invention concerns a high binder flame-retardant (FR)nonwoven fabric that can be employed in many applications, particularlyin household goods, such as stuffing for comforters, pillows, orfurniture; backing for curtains and rugs; and especially for mattressfabrics. The nonwoven fabric comprises from about 6 to about 40 weightpercent of low melt binder (bicomponent fiber or low-melting fiber) andat least one of FR rayon fiber, FR acrylic fiber, FR melamine fiber, FRpolyester fiber, and FR coated fiber; and optionally non-bonding,non-FR, synthetic fiber and/or natural fiber. Nonwoven fabric preparedfrom these components, possessing a batt weight of greater than about 4oz./sq. yd. is capable of passing stringent flame-resistant tests.

2) Prior Art

Flame-retardant (FR) or flame-resistant materials are well known tothose skilled in the textile art. Such materials can be woven ornonwoven, knitted, or laminates with other materials such that they passvarious textile FR or flame-resistant tests, such as California TB 117 &TB 133 for upholstery; NFPA 701 for curtains and drapes; and CaliforniaTB 129 dated October, 1992, concerning flammability test procedures formattresses for use in public buildings. This last test is the moststringent test for mattresses known in the world. Another test forresidential mattresses is California TB603. The criterion for compliancefor TB 603 is as follows:

-   -   Less than 25 MJ of total heat release at 10 minutes after burner        ignition, and    -   Less than 200 kW of heat release rate at 30 minutes after burner        ignition.        Two burners are used to initiate the test. One on the panel,        flame duration of 70 seconds, and one on the border with a flame        duration of 50 seconds. Both are lit simultaneously.

Various FR fibers are well known to those skilled in the textile art. FRfibers based on polyester, rayon, melamine, nylon, acrylic, andpolyolefin fibers such as polyethylene or polypropylene fibers, areknown and commercially available.

U.S. Pat. No. 6,214,058 issued to Kent et al. on Apr. 10, 2001,describes fabrics made from melamine fibers that may or may not beflame-resistant fabrics. This reference describes a process for dyeingmelamine fabrics including blends of melamine and natural fibers (suchas wool or cotton) or other synthetic fibers such as rayon or polyester.As a passing comment, it mentions that the melamine fiber may be FR.

U.S. Pat. No. 6,297,178 issued to Berbner et al. on Oct. 2, 2001,discloses flameproof fabrics based on FR melamine fibers and FR rayonfibers. The melamine and rayon fibers are made FR by coating the fiberswith aluminum.

U.S. Pat. No. 4,863,797 (Sep. 5, 1989); U.S. Pat. No. 5,208,105 (May 4,1993); U.S. Pat. No. 5,348,796 (Sep. 20, 1994); U.S. Pat. No. 5,503,915(Apr. 2, 1996); U.S. Pat. No. 5,513,916 (Apr. 2, 1996); and U.S. Pat.No. 5,506,042 (Apr. 9, 1996) issued to Ichibori et al. disclose an FRcomposite fiber comprising: (A) 85 to 15 parts by weight of a fibercomprising a polymer containing 17 to 86% by weight of a halogen, and 6to 50% by weight of an Sb compound based on the polymer, and (B) 15 to85 parts by weight of at least one fiber selected from the groupconsisting of natural fibers and chemical fibers, the total amount ofthe fibers (A) and (B) being 100 parts by weight.

PCT application WO 03/023108 filed Sep. 11, 2002 in the name of Materand Handermann discloses a highloft FR material composed of FR rayon orFR melamine that are inherently FR. Additionally the application alsodiscloses and requires the use of modacrylic fibers. These materialshave no coating thereon.

In spite of the above-mentioned patents and numerous other nonwoven FRfabrics, there is still a need in the industry to create economicalnonwoven FR articles that pass the stringent guidelines for theCalifornia TB 129 testing as well as other tests for upholstery andcurtains and drapes. Moreover, there is a need in the industry toproduce such a nonwoven article from materials that are relativelyinexpensive and that have light batt weights.

Generally, the California TB 129 test for mattresses states that themattress must char, but not burn through, for a minimum of three minutesbased on certain conditions such as the position of the flame, thetemperature of the flame, the source of fuel being used, etc.Furthermore, after one hour (57 minutes after the flame source has beenextinguished) of burning the test is terminated and certain conditionsmust be met, as more fully set forth herein.

For the California TB 603, the test for mattresses states that twoburners are used to initiate the test. One on the panel, flame durationof 70 seconds, and one on the border with a flame duration of 50seconds. Both are lit simultaneously. Then 10 minutes after burnerignition the mattress must emit less than 25 MJ of total heat release.Also 30 minutes after burner ignition The mattress must emit less than200 kW of heat release rate.

SUMMARY OF THE INVENTION

The present invention relates to nonwoven fabric which is capable ofpassing the California TB 129 test when the nonwoven fabric is employedin a mattress, as well as other tests employed for other household goodslike draperies.

The nonwoven fabric/article of the present invention may be producedfrom a combination of FR synthetic fibers and/or from all naturalfibers. In each case, the nonwoven fabric/article is bonded together bymeans of a low melt binder. The low melt binder may be bicomponent fiberor low-melting fiber. Additionally, the nonwoven article has at leastone of FR rayon fibers, FR acrylic fibers, FR melamine fibers, FRpolyester fibers, and FR coated fibers.

In the broadest sense, the present invention relates to a nonwovenarticle produced from about 6 to about 40 weight percent of low meltbinder; at least one of FR rayon fiber, FR acrylic fiber, FR melaminefiber, FR polyester fiber, and FR coated fiber; and optionallynon-binding, non-FR, synthetic and/or natural fibers.

In the broadest sense, the present invention also relates to a nonwovenarticle produced from a low melt binder, at least two FR fibers of thegroup of FR rayon, FR acrylic, FR polyester, and FR melamine, andoptionally a non-binding synthetic fiber.

In the broadest sense, the present invention further relates to anonwoven article produced from about 6 to about 40 weight percent of lowmelt binder, at least two FR materials selected from the group of FRrayon fibers, FR acrylic fibers, FR melamine fibers, FR polyesterfibers, and FR coated fibers; and a non-binding synthetic or naturalfiber.

In the broadest sense, the present invention still further relates to anonwoven article produced from FR coated fibers, and about 6 to about 40weight percent of a low melt binder.

BRIEF DESCRIPTION OF THE DRAWING

The FIGURE is a graph of heat transmittance temperature in degreesFahrenheit versus weight percent low melt binder for simple rayon/lowmelt binder nonwoven constructions.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The nonwoven article of the present invention is produced from materialsgenerally known to those skilled in the textile art, however, before thepresent invention those materials have not been assembled into anonwoven article like that of the present invention.

FR fibers are grouped into those that are inherently flame resistant,and those that are coated with an FR coating. Inherent FR fibers arethose that have FR features by the end of manufacturing the resin (afterthe resin has initially solidified). FR coated fibers are those thatapply the coating after the resin has initially solidified, or duringthe fiber making process, or after the fiber making process. Suitable FRfibers are those that can pass the various tests set forth below, andmay be either the inherent type or those that are FR coated. FR fibershaving too little flame resistance are not suitable for the presentinvention.

Inherent FR fibers employed in the nonwoven article of the presentinvention are FR rayon, FR melamine, FR polyester, and FR acrylic. Morespecifically, suitable FR rayon is sold under the registered trademark“Visil” by Sateri Oy and distributed by Ventex Incorporated. Visil ispermanently fire resistant (“inherent”) because of the high silicacontent incorporated into the fiber during the manufacturing process ofthe resin. The silica forms an insulating barrier to the source of heat.

Suitable FR melamine fibers are well known in the textile art and can bepurchased, for example, under the trade name “BASOFIL” byMcKinnon-Land-Moran LLC. Like the FR rayon, the inherent FR melaminefibers do not melt or shrink away from a flame, but form a char thathelps control the burn and shield the materials surrounded by fabric.

Suitable inherent FR acrylic fiber is well known to those skilled in thetextile art and sold under the trade name “Modacrylic” distributed byMitsui Textile Corporation and another suitable fiber may also be soldunder the trade name “CEF Plus” by Solutia Inc.

Suitable inherent FR polyester, such as polyethylene terephthalate (PET)with phosphalane (organo phosphorus compound) such as that sold underthe trademark Trevira CS® fiber, or Avora® Plus by Invista are known.

The FR coating employed is a type that has no binding characteristics.It is simply a coating which has an FR component therein, such asphosphorus, a phosphorus compound, red phosphorus, esters of phosphorus,or phosphorus complexes. The FR coating may be based on any materialprovided that it is compatible with the other components mentionedherein for the nonwoven batt. Typically, the FR coating resin is clearor translucent latex (where color is important, or any color and nottranslucent where color is unimportant) and is applied by spraying onthe fiber. A suitable commercially available FR coating resin is knownby the trade name “GUARDEX FR” made by GLO-TEX Chemicals in Spartanburg,S.C. There are several different GUARDEX FR resins and those skilled inthe textile art can pick and choose among them to find that which ismost compatible, taking into account such things as cost, appearance,smell, and the effect it may have on the other fibers in the nonwovenbatt (does it make the other fibers rough, or have a soft hand, ordiscolor the other fibers). The FR coating resin may be applied to thenonwoven batt in a range from about 6 to about 25 weight percent of thenonwoven batt. It is also within the scope of the invention to apply theFR coating to just a portion of the fibers before such fibers areemployed in the nonwoven batt. For example, the FR coating could beapplied to the natural fibers, before they are dry laid/air laid onto aconveyor belt. Nevertheless, when considering the nonwoven batt as awhole, the amount of the FR coating remains within the range of 6 to 25weight percent of the nonwoven batt. More typically the Fr coating isapplied in a range from about 10 to about 18% by weight of the fibers towhich it is applied.

The GUARDEX FR products are generally cured at about 300 degreesFahrenheit, or preferably lower to minimize yellowing. Although thisproduct must be cured, it has no significant binding effect on the otherfibers in the nonwoven batt. It is merely cured to the fibers themselvesso that it provides an FR characteristic to the fibers in addition toany FR characteristics or lack thereof of the fibers that are in thenonwoven batt.

While the above FR product (GUARDEX) is a liquid product applied as aspray, other FR resin in solid form may be applied as a hot melt productto the fibers, or as a solid powder which is then melted into thefibers.

The FR fibers come in different deniers from approximately 1.5 to about10 dpf (denier per filament).

The low melt binder may be either a bicomponent fiber, for example, or alow melt polymer fiber. The low melt binder is generally employed in arange of from about 5 to about 50 weight percent of the nonwoven batt.The bicomponent fiber generally contains a low melt portion and a highmelt portion. Consequently, the bicomponent fiber may be either theside-by-side type wherein the low melt component is adjacent to highmelt component, or the sheath-core type wherein the high melt componentis the core and the low melt component forms the sheath. Suchbicomponent fibers are well known to those skilled in the textile artand may be based upon polyolefin/polyester, copolyester/polyester,polyester/polyester, polyolefin/polyolefin, wherein the namingconvention is the low melt component followed by the high meltcomponent. In those types wherein it is polyester/polyester, orpolyolefin/polyolefin, the high melt component has at least 5 andpreferably 8 degrees Fahrenheit higher melt temperature than the lowmelt temperature. More specifically, for example, apolyolefin/polyolefin could be polyethylene/polypropylene. Suitablebicomponent fibers are preferable a 50:50 low melt portion to high meltportion. But the present invention also contemplates a broader range of20:80 to 80:20 for the bicomponent fiber.

Where the low melt binder is a low melt polymer fiber, those fibersmentioned above with respect to the low melt component of thebicomponent fiber are also suitable low melt polymer fibers. In otherwords, the low melt polymer fiber may be copolyester, or polyolefin,such as polyethylene. Lastly, the low melt binder may also be latexsprayed onto the nonwoven batt. In this situation, the latex employedhas a low melt temperature so that once the latex is sprayed on to thenonwoven fiber batt, it can be cured by means of heat (subjecting thenonwoven batt to an oven for a short period of time sufficient to curethe latex). Such low melt binders are well known to those skilled in thetextile art.

It is within the scope of the present invention to provide a low meltbinder in the form of latex. Such products are well known andcommercially available. It is also known to make an FR resin in the formof latex. Those skilled in the textile art recognize that it may bedesirable to combine low melt binder latex with FR resin latex and applysuch a product to the nonwoven batt by spraying.

Suitable non-FR synthetic fibers can be polyester such as polyethyleneterephthalate (PET) or a copolyester, rayon, nylon, polyolefin such aspolyethylene fibers, acrylic, melamine, and combinations of these. Othersynthetic fibers not mentioned may also be employed. When non-FRsynthetic fibers are employed, they give the batt certaincharacteristics like loft, resilience (springiness), tensile strength,and thermal retention, useful for household goods. Preferred are PET andrayon fibers.

Natural fibers may also be employed in the nonwoven batt of the presentinvention. Natural fibers such as flax, kenaf, hemp, cotton, and woolmay be employed, depending on the properties desired. Preferred are flaxand kenaf.

Because the synthetic fibers and natural fibers are non-binding and arenot flame resistant, such fibers can be used to dial-in desiredcharacteristics and cost. As such it is also within the scope of thepresent invention to employ a mixture of synthetic and natural fibers.

Currently, there are no regulations in effect for mattresses for home(residential) use. However, California is considering drafting suchregulations and many industry experts say that such proposed regulationswill mirror California TB 129. The strictest flame-resistant test formattresses is the state of California, Department of Consumer Affairs,Bureau of Home Furnishings and Thermal Insulation, Technical Bulletin129. The purpose of this test is to set a standard for the behavior ofmattresses used in public occupancy such as hotels, motels, dormitories,prisons, etc. Specifically, this test measures the mattress when it issubjected to a specific flaming ignition source under well-ventilatedconditions. Under such conditions, it should char but not support flamefor at least 3 minutes. The California TB 129 test specifies a fabricwrapped around foam with a horizontal flame at 1800 degrees Fahrenheitfor 3 minutes. There can be no drips, and the fabric must contain thefoam although the foam may be melted or partially melted. The fabriccannot let the flame reach and ignite the foam.

The nonwoven batt of the present invention may be constructed asfollows. The various combinations of fibers that can be employed in thepresent invention may be weighed and then dry laid/air laid onto amoving conveyor belt, for example. The size or thickness of a nonwovenbatt is generally measured in terms of ounces per square yard. The speedof the conveyor belt, for example, can determine or provide the desiredbatt weight. If a thick batt is required, then the conveyor belt movesslower than for a thin batt. The weight percent of the total fibers inthe batt is 100 percent. This does not include the weight of the FRresin since it is not in fiber form. It does, however, include thebicomponent fibers.

Suitable nonwoven fabrics of the present invention have a batt weightgreater than about 4 oz./sq. yd. Preferably the batt weight ranges from4 oz./sq. yd. to 20 oz./sq. yd., with the most preferred range being 6oz./sq. yd. to 9 oz./sq. yd. Using a batt weight greater than about 20oz./sq. yd. offers no significant improvement in performance and is morecostly. If desired, any rearrangement of the fibers such as by cardingoccurs next. Then the conveyor belt moves to an area where any spray-onmaterial is added to the nonwoven batt, for example, the FR coatingsprayed onto the nonwoven batt as a latex while the batt is stillpositioned on the conveyor belt. If the conveyor belt is foraminous, theexcessive latex FR resin drips through the belt and may be collected forreuse later. Once all the sprayed-on materials have been applied, ifany, the conveyer belt can then move the nonwoven dry laid batt to anoven for melting and curing the low melt component of the bicomponentfiber or the low melt polymer fiber. The residence time in the ovendepends on the fibers employed and is easily determinable by one skilledin the textile art. Thereafter, the nonwoven batt is cooled so that anylow melt binder material re-solidifies thus locking the fibers employedinto a solid batt. Thereafter, the batt may be cut to any size desiredto serve as mattress fabric or other purposes such as stuffing forcomforters, pillows, and furniture.

General Procedures

Various fiber components, some FR fibers and some synthetic fibers(primarily employed for increasing physical properties of the nonwovenbatt), are set forth in the various examples having a range of dpfbetween 1.5 and 10, as mentioned previously. Also, the weight of thefiber batt as well as the burn test results according to California TB129, measured in seconds, are set forth in the examples.

More specifically, for Example 3, the specimen consisted of a twin-size,innerspring mattress and foundation set. The specimen was covered with awhite/off-white-colored ticking material. The construction of themattress is well described in California TB 129.

The test specimen, after conditioning to 73 degrees and 50 percentrelative humidity was placed on a steel frame on a load cell platformalong the far side of the test room. The specified propane burner wasplaced centrally and parallel to the bottom horizontal surface of themattress 1 inch from the vertical side panel of the mattress. Thecomputer data acquisition system was started, then the burner wasignited and allowed to burn for 180 seconds. The test was continueduntil either all combustion ceased, or one hour passed.

The specimen does not meet the test requirements if any of the followingcriteria are exceeded:

-   -   1. Weight loss of 3 lbs or greater in the first 10 minutes;    -   2. Maximum rate of heat release of 100 KW; or    -   3. Total heat release of 25 MJ in the first 10 minutes.

For Example 5, a pair of twin mattresses was tested under California 603for residential use. The criterion for compliance for TB 603 is asfollows:

-   -   Less than 25 MJ of total heat release at 10 minutes after burner        ignition, and    -   Less than 200 kW of heat release rate at 30 minutes after burner        ignition.        This test does not require a weight loss characteristic like the        TB 129.

Heat transmittance value is indicator of how much heat is transferredfrom one side of the nonwoven batt to the other, opposite side, forgiven period of time and under certain heating conditions. The value,expressed as a temperature, is the temperature of the side of thenonwoven farthest from the flame. The best result is the lower valueresult, indicating the nonwoven is a great insulator. Specifically, thebarrier specimen is in a horizontal fixed position. A burner is locatedbeneath the specimen. The distance from the top of the burner to thespecimen is 49 mm. The propane flow rate is controlled to 1.25 standardcubic feet per hour. An infrared temperature gun, with an emissivity of0.95, is used to measure the temperature on the opposite side of thespecimen. The temperature is recorded every 10 seconds for a duration of90 seconds. The maximum temperature recorded between 40 seconds and 90seconds is given as the test result.

EXAMPLE 1

Various combinations of FR fibers with other synthetic and/or naturalfibers such as rayon, PET, flax, and kenaf were produced. The variousfibers were dry laid onto a moving conveyor belt as is known in thetextile art. For Samples 1-6 and 11, where an FR resin was employed, itwas sprayed on to the nonwoven fiber batt. The nonwoven fiber batt wastransported via the conveyor belt to an oven such that the low meltcomponent melts. Then the fibers were transported to a cooling areawhere the low melt component of the low melt binder re-solidified thuslocking the various fibers into a unitary structure as a batt. Thesevarious nonwoven batts, at various weights, were then subjected to aburn time test similar to the California TB 129 test. In the test, thenonwoven fabric was wrapped once around the foam. A flame was applieddirectly to the nonwoven fabric for at least 300 seconds and thestructural integrity was noted. All of the test samples maintained theirstructural integrity for at least the time indicated, and the flame didnot reach the foam. The burn time is listed in seconds. The batt weightis listed in ounces per square yard.

In all samples where FR resin was employed (Samples 1-6 and 11), GUARDEXFR resin was used. The FR resin, because it is sprayed on, is based onthe total weight of the fibers that are employed to make up the nonwovenbatt. In all samples, a bicomponent fiber comprising a low melt sheathcomponent of copolyester and a high melt core component of PET wasemployed. In Samples 2, 4, and 9 the FR acrylic employed was 7 dpf(denier per filament). In Sample 7 the dpf of the FR acrylic was 5, andin Samples 3, 5, and 10 the dpf was 2. The dpf of the FR rayon inSamples 4 and 9 was 3.5. In Sample 8 it was 5 dpf, and in Samples 5 and10 it was 8 dpf. The nonwoven batt construction and results are setforth below in Table 1. TABLE 1 FR FR FR FR Batt weight Burntime SampleRayon Acrylic Melamine Rayon PET Resin* Bico (oz/yd²) (seconds) 1 50 35(21) 15 8.67 605 2 30 25 30 (14) 15 8.5 623 3 30 25 30 (20) 15 8.6 941 430 30 25 (15) 15 8.9 **1200   5 30 30 25 (14) 15 8 **1200   6 80 (24) 209.5 600 7 40 40 20 5.9 307 8 40 45 15 5.1 451 9 30 30 25 15 8.9 **360 10  30 30 25 15 8 **360  11  25% Flax; 25% Kenaf 35   (20)*** 15 11.7**360 *Weight % based on weight of all other components.**The burn time was terminated because it had more than passed the test.In all other instances the burn time test was permitted to go tocompletion (i.e. where the flame burned through the nonwoven materialsuch that it could no longer contain the liquefied foam.).***Weight % based on the weight of natural fibers only.

EXAMPLE 2

Sammple 2 was a repeat of Samples 1, 5, 6, and 8-10 and theircorresponding burn time tests, except that in Samples 1 and 5 the amountof bicomponent employed was 20 weight percent, while the amount of PETemployed was 5 weight percent less. In each instance, the burn time inseconds was stopped at 600 seconds. 600 seconds is more than 3 timeslonger than what is required by California TB 129. The results are setforth in Table 2 below. TABLE 2 FR FR FR FR Batt weight Burntime SampleRayon Acrylic Melamine Rayon PET Resin* Bico (oz/yd²) (seconds) 1 50 15(21) 20  8.67 **600 5 30 30 15 (14) 20 8   **600 6 80 (24) 20 9.5 **6008 40 45 15 5.1 **600 9 30 30 25 15 8.9 **600 10  30 30 25 15 8   **600

While this result is consistent for Samples 1 and 6, the retest ofSample 8 gave a slightly stronger result.

EXAMPLE 3

A nonwoven batt similar to Sample 5 was made, except that 20 weightpercent FR resin was sprayed onto the batt (instead of 14 weightpercent, as in Sample 5). The batt weight was 5.85 oz./sq. yd. (insteadof 8 oz./sq. yd., as in Sample 5). A twin size mattress was constructedas described in the General Procedures and more specifically inCalifornia TB 129. This mattress was subjected to the full FlammabilityTest Procedure for Mattresses for Use in Public Buildings specified inthe General Procedures and more specifically in California TB 129. Thetest results are reported below.

The ambient temperature was 75 degrees Fahrenheit with a relativehumidity of 50 percent. After the test, the specimen was removed fromthe test room and was damaged in the following manner: Ticking Material40% consumed. Internal Components 50% consumed. Barrier Material Intact.Foundation 65% consumed.

The results of the test were as follows: Time (Min:Sec) Observations 0.00 The test was started.  0:05 The ticking material began to char. 0:08 The ticking material ignited.  0:45 The flames began to propagateacross the top panel.  3:00 The propane test burner was turned off. 3:30 The flames began to propagate across the front side of foundation. 8:30 Flaming drops began to fall from the left handle of the mattress.10:10 Flaming drops ceased from the left handle. 14:50 Flaming dropsbegan to fall from the right handle. 23:15 The flames reached the leftfront corner of the mattress. 45:42 The flames began to decrease on theleft corner of the mattress. 50:00 The flames reached the right frontcorner of the mattress. 53:49 The flames reached the right rear cornerof the mattress. 57:30 Flaming drops began to fall from the left rearcorner of the mattress. 60:00 Test terminated/specimen extinguished.Peak Rate of Heat Release = 40.60 KWTotal Heat Release = 8.60 MJWeight Loss in First 10 Minutes = 0.5 lbs.

A weight loss of 3 lbs. or more in the first 10 minutes is a testfailure. For this Example, the result of 0.5 lbs. is excellent. A testfailure also occurs if the maximum rate of heat released exceeds 100 KW.For this Example, the result of 40.60 KW is excellent. A test failureoccurs if the total heat release is 25 MJ or more in the first 10minutes. For this Example the result was 8.60 MJ. This was excellent.

EXAMPLE 4

In this example, the nonwoven batt includes either 30 or 40 weightpercent low melt binder (bicomponent fiber or low-melting fiber) and 60or 70 weight percent FR coated rayon. The FR rayon was coated with 15weight percent add-on FR coating resin from Glotex-Glotard FFR. The battweight was 9 oz./sq. yd. in both cases. The 40/60 batt had a heattransmittance value of 560° Fahrenheit as measured by an infraredtemperature measurement device. The 30/70 batt had a heat transmittancevalue of about 520° Fahrenheit.

Generally for simple nonwoven batts constructed from low melt binder andFR coated rayon, there appears to be a “sweet spot” in terms ofperformance between 15% and 25% low melt binder, as illustrated in theFIGURE. Although there is a performance deterioration after about 30%low melt binder, such simple construction nonwovens are capable ofpassing the above identified tests. Therefore it offers a low costsolution for manufacturing FR mattresses, for example.

EXAMPLE 5

Two twin size mattresses were constructed and tested under TB 603testing conditions. The construction of the barrier and the results fromthe test are set forth below.

Mattress Barrier Blends #1:

-   -   a. Panel—70% treated rayon and 30% low melt.    -   b. Border—70% treated rayon and 30% low melt    -   c. Construction—Mattress was a two-sided, baseline-3, tight top        produced by Restonic Mattress Corporation.    -   The TB603 data was as follows;        -   10-minute total heat release—1.07 MJ        -   30-minute heat release rate—0 kW.            Mattress #1 passed the TB 603 tests.

Mattress Barrier Blends #2:

-   -   d. Panel—70% post treated cotton and 30% low melt

e. Border—70% post treated rayon and 30% low melt

f. Construction—Mattresses were two-sided, baseline-3, tight topproduced by Restonic Mattress Corporation.

-   -   The TB603 data was as follows;        -   10-minute total heat release—2.15 MJ for Mattress 1 and 1.61            MJ for Mattress 2        -   30-minute heat release rate—35 kW for Mattress 1 and 25 kW            for Mattress 2.            Mattress #2 did not pass the TB 603 test.

Thus, it is apparent that there has been provided, in accordance withthe present invention, a nonwoven fabric that fully satisfies theobjects, aims, and advantages set forth above. While the presentinvention has been described in conjunction with specific embodimentsthereof, it is evident that many alternatives, modifications, andvariations will be apparent to those skilled in the textile art in lightof the foregoing description. Accordingly, it is intended to embrace allsuch alternatives, modifications, and variations as fall within thespirit and broad scope of the present invention.

1) A nonwoven article produced from greater than about 25 to about 40weight percent of a low melt binder; at least one of FR rayon fiber, FRacrylic fiber, FR melamine fiber, FR polyester, and FR coated fiber; andoptionally a non-bonding synthetic or natural fiber, wherein saidnonwoven article has a batt weight of at least 4 oz./sq. yd. 2) Thenonwoven article of claim 1, wherein said non-bonding synthetic fiber isone of rayon, polyester, and a mixture thereof. 3) The nonwoven articleof claim 1, wherein said nonwoven article is produced from at least twoof FR rayon fiber, FR acrylic fiber, FR melamine fiber, FR polyesterfiber, and FR resin. 4) The nonwoven article of claim 1, wherein saidlow melt binder is one of a bicomponent fiber, a low melting fiber, anda mixture thereof. 5) The nonwoven article of claim 4, wherein saidbicomponent fiber has a polyester component and one of a polyolefincomponent, a copolyester component, and a mixture thereof. 6) Thenonwoven article of claim 4, wherein said low melting fiber is one of acopolyester fiber, a polyolefin fiber, and a mixture thereof. 7) Thenonwoven article of claim 1, wherein said FR coating is a resin of aphosphorus compound, red phosphorus, phosphorus, or a mixture thereof.8) The nonwoven article of claim 1, comprising about 30 weight percentof said low melt binder. 9) The nonwoven article of claim 1, comprisingabout 40 weight percent of said low melt binder. 10) The nonwovenarticle of claim 1, wherein said natural fiber is one of flax, kenaf,and a mixture thereof. 11) A mattress comprising a nonwoven articleproduced from greater than about 25 to about 40 weight percent of a lowmelt binder; at least one of FR rayon fiber, FR acrylic fiber, FRmelamine fiber, FR polyester fiber, and FR coated fiber; and optionallya non-bonding synthetic or natural fiber, wherein said nonwoven articlehas a batt weight of at least 4 oz./sq. yd.